[PATCH 4/6] kexec: A new system call, kexec_file_load, for in kernel kexec

[Vivek Goyal]

On Thu, Nov 21, 2013 at 05:03:11PM -0800, Kees Cook wrote:
> Hi,
> 
> On Thu, Nov 21, 2013 at 11:03:50AM -0800, Greg KH wrote:
> > On Wed, Nov 20, 2013 at 12:50:49PM -0500, Vivek Goyal wrote:
> > > This patch implements the in kernel kexec functionality. It implements a
> > > new system call kexec_file_load. I think parameter list of this system
> > > call will change as I have not done the kernel image signature handling
> > > yet. I have been told that I might have to pass the detached signature
> > > and size as part of system call.
> > 
> > This could be done as we do with modules, and just tack the signature
> > onto the end of the 'blob' of the image.  That way we could use the same
> > tool to sign the binary as we do for modules, and save the need for
> > extra parameters in the syscall.
> 
> As long as the system call passing in an fd, I'm all good. For those
> of us that run from verified filesystems, we don't need the additional
> signing overhead, but we do need the file descriptor to validate the
> origin of the kernel.

Yep, Greg had mentioned that keep the interface file descriptor based so
that it can work well with LSM hooks and that's why I went with it.

Thanks
Vivek